Airline passengers headed for the United States faced tighter security measures on Saturday after an attempt to blow up a U.S. jet bound for Detroit, including pat-downs and an order to stay seated during the last hour of flight, airlines and security officials said.

Air Canada advised U.S.-bound travelers to arrive early at airports to allow extra time for security screenings, including additional personal searches.

“Passengers should also expect flight delays, cancellations and missed connections, and limit themselves to a single piece of carry-on baggage,” Canada’s largest airline said on its website.

“New rules imposed by the U.S. Transportation Security Administration also limit on-board activities by customers and crew in U.S. airspace that may adversely impact on-board service,” Air Canada said.